The manufacturer use-instructions for this item are just wrong :
Shall One Add an Agar-Agar Amount Greater than 1.5 tsp. (teaspoon) to a "US Pint" (~473ml) Volume of Liquid, the outcome will usually be a Rock-Hard & Uneatable Hydrate ! (so hard that it might require a knife to handle it properly)
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Also, when boiled (while submerged in liquid), it emits an unpleasant potent algae/sea smell.